@article {3225, title = {Thermal limit for metazoan life in question: in vivo heat tolerance of the Pompeii worm.}, journal = {PLoS One}, volume = {8}, year = {2013}, month = {2013}, pages = {e64074}, abstract = {

The thermal limit for metazoan life, expected to be around 50{\textdegree}C, has been debated since the discovery of the Pompeii worm Alvinella pompejana, which colonizes black smoker chimney walls at deep-sea vents. While indirect evidence predicts body temperatures lower than 50{\textdegree}C, repeated in situ temperature measurements depict an animal thriving at temperatures of 60{\textdegree}C and more. This controversy was to remain as long as this species escaped in vivo investigations, due to irremediable mortalities upon non-isobaric sampling. Here we report from the first heat-exposure experiments with live A. pompejana, following isobaric sampling and subsequent transfer in a laboratory pressurized aquarium. A prolonged (2 hours) exposure in the 50-55{\textdegree}C range was lethal, inducing severe tissue damages, cell mortalities and triggering a heat stress response, therefore showing that Alvinella{\textquoteright}s upper thermal limit clearly is below 55{\textdegree}C. A comparison with hsp70 stress gene expressions of individuals analysed directly after sampling in situ confirms that Alvinella pompejana does not experience long-term exposures to temperature above 50{\textdegree}C in its natural environment. The thermal optimum is nevertheless beyond 42{\textdegree}C, which confirms that the Pompeii worm ranks among the most thermotolerant metazoans.

}, keywords = {Adaptation, Physiological, Animals, Environment, Controlled, Gene Expression Profiling, Heat-Shock Response, Hot Temperature, HSP70 Heat-Shock Proteins, Molecular Sequence Data, Polychaeta, Pressure, Reverse Transcriptase Polymerase Chain Reaction, Temperature}, issn = {1932-6203}, doi = {10.1371/journal.pone.0064074}, author = {Juliette Ravaux and Hamel, G{\'e}rard and Magali Zbinden and Tasiemski, Aur{\'e}lie A and Boutet, Isabelle and Nelly L{\'e}ger and Arnaud Tanguy and Jollivet, Didier and Bruce Shillito} }